Clock-striking mechanism



Feb- 24 1931` L. GIANFRANCESCH:

CLOCK TRIKING MECHANISM Filed Feb. 9. 1927.' 2 Shae'tS-She NNW" NVENTOR .in Q @a fag/Tra Feb- 24, l93ll.. GIANFRANcr-:scHl

cLocK STRIKING MEGHANISM Filed Feb. 9. 1927 2 Sheets-Shea? 2 INVENTOR '12 0 ('z'anfran Cesc t z' Patented Feb. 24, 1931 UNITED STATES LINO GIANFRANCESCHI, OF WEST HAVEN, CONNECTICUT CLOCK-STR-IKING MECHANISM Application filed February 9, 1927.

rIhis invention relates to clocks, and more particularly to a clock having mechanism for striking the hour and quarter-hours.

One object of this invention is to provide a clock of the above nature in which the striking mechanism is energized by the same spring which drives the time-keeping mechanism.

A further object of this invention is to provide a striking mechanism for a clock of the above nature adapted to be selectively operated at the will of the user so as to audibly indicate the time at any instant of the day or night.

A further object is to provide a clock of the above nature having means for silencing the striking mechanism.

A further object is to provide a device of this nature which will be relatively simple in 20 construction, inexpensive to manufacture, ornamental in appearance, and very efficient in use.

With these and other objects in view there has been illustrated on the accompanying 25 drawing one form in which the invention may be conveniently embodied in practice.

Fig. 1 represents a front view of the clock as it appears when the crystal and dial have been removed.

Fig. 2 is a side view of the same shown partly in section and with certain parts broken away.

Fig. 3 is a rear view of the clock as it appears when the casing has been removed.

Fig. 4 is a similar rear view of the clock with parts broken away and with the casing and base removed.

Fig. 5 is a fragmentary side sectional view of the lower portion of the clock mechanism 0 showing a portion of one of the striking tongs.

Referring now to the drawings in which like reference numerals denote corresponding parts throughout the several views, the

numeral 10 indicates the base of the clock, said base supporting a casing 11 having a top 12, said top having a pair of posts 12a in which a U-shaped handle 13 is pivoted.

Mounted upon the base 10 within the casil ing 11 is a clock-work carried by a front Serial No. 166,926.

plate 14 and a rear plate 15, said plates being connected together by the usual horizontal pillars 16. The front of the casing 11 is closed by the usual glass crystal 17 behind which is a usual dial 18.

Provision is also made of the usual hour hand 19 mounted on a tubular shaft 20, and the usual minute hand 21 mounted on a solid shaft 22 located within the tubular shaft 20. The shafts and 22 are driven from the main shaft 23 through suitable gearing, as clearly shown in Figs. 1 and 2. The main shaft 23 is driven by a main spring 24.

As most clearly shown in Figs. 3 and 4, the minute hand shaft 22 is provided on its rear end with a cam member 25 having a plurality of stepped sectors 26, 27, 28, and 29, said sectors being progressively smaller in diameter. The ends of said sectors form shoulders 31, 29a, 30, and 30a, said shoulders being adapted to be engaged by a pin 32 on a spring arm 33, the latter being pivotally connected to a bell-crank lever 34 mounted on a shaft 35 journaled between the plates 14 and 15. The shaft 35 is actuated by a helical spring 36 having its ends connected to the plate 14 and the shaft 35 respectively.

The bell-crank lever 34 is provided with a substantially horizontal T-shaped arm 37 having an arcuate toothed segment 38 on its end for engagement with a pinion 39 operatively connected by a ratchet 40 and a pawl 41 with a gear 42 meshing with a pinion 43 mounted on shaft 44. The shaft 44 also carries a gear 45, the teeth of which mesh with a worm gear 46 having an air-controlled fly-wheel governor 47 rigidly secured thereto.

By means of this construction, after the bell-crank lever has been moved until its horizontal arm 37 is in its uppermost position, at which time the cam 25 will engage the pin 32 of the spring arm 33, the helical spring 36 in unwinding will force the bellcrank rlever downwardly in a .clockwise direction. The speed of this rotation will be determined by the governor 47 and the retardation of a curved spring-pressed brake arm 48 pivoted on a pin 49 on the frame 15. The brake arm 48 is pressed to the left, as viewed in Figs. 3 and 4, by a. wire spring 50 engaging apin 50a, and said brake arm 48 has a flat end 51 for engaging an eccentric collar 52 rotatably mounted on the horizontal arm 37.

In operation, the flat end 51 of the springpresse-d brake arm 48 will press against the eccentric collar 52 and serve as a brake upon the motion of the bell-crank lever. Integrally secured to the eccentric collar 52 is a depending detent arm 53 having a shoulder 54 intermediate its ends. The shoulder154 i-s adapted norn ally to be'engaged by one of a series of pins 55, 56, 57, and 58, on the eXtremities of a star-wheel 59, the latter being mounted upon the minute-hand shaft 22.'

During the normal operation of the timekeeping mechanism7 the rotation of the minute-hand shaft 22will raise the detent arm 53, and cause it to move in a clockwise direction, at the same time 'forcingv the bell-crank lever 34 upwardly in a counter-clockwise direction. This action will continue Auntil the detent arm 53 is engaged andrheld by a pin yon th-e plate 15 and the parts will then be in the position shown in Fig. 3. Further rotation of the minute-hand shaft 22 will cause the particular pin 55, 56, 57, or 58, as the case may be, to ride off the shoulder 54 of the detent arm 53. Thereupon the bellcrank lever 34 will be released, and the helical spring 36 will be free to act to move said bell-crank lever in a clockwise direction for operating the striking mechanism.' I

It will be noted from the drawing that the pins 55, 56,57, and 58 are spaced atdilferent increasing radial ldistances from the center shatt 22. By means of this construction, the detent arm 53 will engage the pin 60 at the same instant as the pin 32 abuts against the shoulder on the snail cam 27, each pin 55, 56,

57, and 58 being sospaced from the shaft. 22 that it will raise the segment'the proper distance for each quarter hour. Y

The bell-crank lever 34 has a vertical lower substantially S-shaped arm 61, on the eXtremity of which is an arcuate toothed segment 62, the teeth of which (fifteen in all) are adapted to successively engage a lug 63 on one end of ank angle lever 64. counter-weight 65 on its other end and is adapted to engage a pin 66 forming part 0f an hour-striking member 67. y The hourstriking member 67 has a depending tong 68 for engagement with an hour gong 69.V

Mounted upon the toothed segment 62 is a shorter segment 70 having three teeth, said segment 70 lying in dierent plane from Y the segment 62 and being in alinement with a lug 7l of an angle lever 72 similar to the lever 64 previously describedY The lever 72 has a counterweight 7 2a and is adapted to engage a pin 73 of a quarter-hour-striking member 74', the latter being provided with a depending tong 75 for striking the quarterhour gong 76.

rlhe lever 64 has a smallv As will be clear from Figs. 3 and 4, a space equal to the width of about two teeth is left on the segment 62 between the third and fourth teeth thereof,and the lugs 63 and 71 are so spaced that while the lug 63 is engaging the first tooth of the short segment 70, the lug 71 will almost but not quite simultaneously engage the first tooth of the segment 62.

By means of this construction, assuming that the minute hand has just passed the threequarter hour position, the lirst three strokes of the hour7 gong 69 will occur at about the same time as the three strokes ofthe quarter-hour gong 76, thus producing a pleasing blended tone or chord. Thev bellcrank lever 34 will then continue to move in a clockwise direction and after a short interval the teeth of the hour-striking segment 62 will successively engage the lugv 63 and cause the hour gong to be struck a number of'rtimesY corresponding to the correct hour.

ln order to limit the downward motion of the bell-crank lever 34 so that only the correct number of strokes ofn the hour gong will occur, provision is made of a snail cam 77 arranged in front of the plate 14 and journaled on a shaft 78 which is geared' in any suitable manner to the hour-hand shaft 20. rlhe snail cam 77 is providedin its periphery with aseries ofeleven lugs 79 arranged at successively greater distances fromvthe center of said cam and the twelve faces ofl said cam between said lugs 7 9are adapted to be engaged by a linge-rl79a projecting from an arm 8O of a lever 81 rigidly secured' to the bell-crank lever shaft 35 andl located in front of the plate 14. crank lever in a clockwise direction is thereby limitedI to the correct ,amount depending on the hour ofv the day. The lever 81 has a short arm 82opposite the arm 80 to which is pivoted an upwardly extending rod 83- by means of which the user may at any time ascertain the time of the day by pushing down on aknob 84onthe top of said rod. 83, said knob being locatedV above the. coverr 12.

In order to hold the' shaft 78 from accidental movement outV of proper position. the

snail cam shaft 78 is provided in front of theY plate 14 with a toothed wheel 85 adapted to be engaged at all times bya leaf-spring 86, the end 87 of which is V-shaped in order to lit between adjacent teeth of said wheel 85. The leaf spring 86 thus serves to hold the snail cam 7 9 in its proper positions` and thus insures the correct rotation of the bell-crank lever 34. whenever the striking mechau'smv is operated.

' In order to cause the snail cani one notch after` each revolution of t lar hour-shaft 20, said hour-shaft 26 ha pointed arm88 rigidly mounted thereon,

said

arm 88 being in alinement with the teeth of the toothed wheel85.` By means of this con*- The rotation of?A the' belly struction, it will be evident that at each revolution of the hour-hand shaft 20, the arm 88 will engage one of the teeth 'T9 of the wheel S5 and rotate it one-twelfth of a revolution, the leaf-spring 86 rising and permitting this action to occur.

In order to permit the striking mechanism to be silenced whenever desired, provision niade of a bifurcated lever 89 pivoted at 99 on the rear plate l5, as clearly shown in 3 and fi. The Jever 89 is provided with a pair of upwardly extending pointed lugs 91 and 92 for engaging the pins 6G and 73 of the striking tongs 68 and 75 respectively and forcing them into inactive position..

The silencing mechanism is adapted to be operated by an upwardly extending arm 93, the latter being pivotally connected to the end of the arm 89 and having an operating knob 94 at its upper end above the cover 1Q. Extending horizontally from the ver yical rod 93, provision .is made of an adjustable crossrod said cross-rod being held in place by a set Screw 96 and having an arm 9'? adapted to engage pin 98 on the detent arm whereby said detent arm 53 will be moved upwardly into contact with a pin 99 on the arcuate gear segment 38, as clearly shown in Fig. 4. The bell-crank lever 34 will' thus be locked against downward rotation, the friction between the silencing lever 89 and the plate l. being sufiicient to hold it in silencing posiiion.

IVhile there has been disclosed in this specification one form in which the invention may be embodied, it is to be understood that this form is shown for the purpose of illustration only, and that the invention is not to be limited to the specific disclosure but may be modified and embodied in various other forms without departing from its spirit. In short` the invention includes all the modifications and embodiments coming within the scope of the following claims.

Having thus fully described the invention, what is claimed as new, and for which it is desired to secure Letters Patent, is:

l. In a clock, a frame, a time-keeping mechanism carried by said fra-me and having a main-spring-driven shaft, a spring-pressed lever pivoted in said frame on an axis spaced from said shaft, said lever having means at its lower end for operating a strike mechanism, a detent arm pivoted to the upper part of said lever, a member secured to said shaft having a pin for engaging said detent arm to cause said lever to move in one direction, and a pin extending from said frame and lyino in the path of said detent arm to release said arm from engagement with the pin on said member to permit said lever to be moved by its spring in the opposite direction forl operating the strike mechanism.

2. In a clock, a frame, a time-keeping mechanism carried by said frame and having a main-spring-driven shaft, a spring-pressed lever pivoted in said frame on an axis spaced from said shaft, said lever having a segment at its lower end for operating a strike mechanism, a detent arm pivoted to the upper part of said lever, a member secured to said shaft having a pin for engaging said detent arm to cause said lever to move in one direction, and a pin extending from said frame and lying in the path of said detent arm to release said arm from engagement with the pin on said member to permit said lever to be moved by its spring in the opposite direction for operating the strike mechanism.

3. In a clock, a frame, a time-keeping mechanism carried by said frame and having a main-spring-driven shaft, a spring-pressed lever pivoted in said frame on an axis spaced from said shaft, said lever having means at its lower end for operating a strike mechanism,a detent arm pivoted to the upper part of said lever, a member secured to said shaft having a pin for engaging said detent arm to cause said lever to move in one direction, and means extending from said frame and lying in the path of said detent arm to release said arm from engagement with the pin on said member to permit said lever to be moved by its spring in the opposite direction for operating the strike mechanism.

4. In a clock, a frame, a time-keeping mechanism carried by said frame and having a main-spring-driven shaft, a spring-pressed bell-crank lever pivoted in said frame on an axis spaced from said shaft, said lever having means at its lower end for operating a strike mechanism, a detent arm pivoted to the upper part of said lever, a member secured to said shaft having a pin for engaging said detent arm to cause said lever to move in one direction, and a pin extending from said frame and lying in the path of said detent arm to release said arm from engagement with the pin on said member to permit said lever to be moved by its spring in the opposite direction for operating the strike mechanism.

In testimony whereof, I have affixed my signature to this specification.

LIN() GIANFRANCESCHI. 

